1. Technical Field
The present invention relates generally to junction adapters for use in a conventional plural line clamping system and, more particularly, to junction adapters which have axial extension portions which project axially outwardly from a central support portion so that the locking nuts for the fluid connections to the junction adapters, especially those having face seal connections, are made more easily accessible by a standard wrench or like tool.
2. Discussion
Plural line clamping systems are widely used in hydraulics applications whenever it is necessary to connect a plurality of fluid lines to a machine. The plural line clamping system is a mounting device for holding the connectors that connect the fluid lines from the machine to the fluid lines heading to the source of fluid power. These connectors are commonly known as junction adapters. The plural line clamping system provides a secure mount for the junction adapters so that they will not shake loose or rattle. Plural line clamping systems and a variety of junction adapters used with them are disclosed in U.S. Pat. Nos. 3,397,431, 3,414,220 and 4,878,696, as well as in copending U.S. patent application Ser. No. 07/733,344, all in the name of William Ray Walker, an inventor of the present invention, and assigned to Hydro-Craft, Inc., of Rochester Hills, Mich., the assignee of present invention. These patents and application are hereby incorporated by reference.
Since their introduction, plural line clamping systems such as those available from Hydro-Craft, Inc. and sold under the trademark MULTI-CLAMP.RTM., have become quite popular and are widely used in the machine tool industry to route and secure hydraulic and pneumatic piping, tubing and other lines in an orderly, neat and efficient manner. The MULTI-CLAMP.RTM. system is widely used in nearly every hydraulics application to secure a plurality of fluid lines. There are currently several tens of thousands of MULTI-CLAMP.RTM. systems in use in the United States and other countries, and MULTI-CLAMP.RTM. systems in several standard sizes have been marketed for years by the assignee of the present invention.
In general, each of these plural line clamping systems includes two U-shaped, stamped metal channels which oppose one another. The channels are formed with semi-cylindrical collars that support the junction adapters at cylindrical collar support portions formed on the junction adapter. As can be seen from the prior patents, the plural line clamping system can typically have four to ten or more opposing pairs of semi-cylindrical collars, each pair capable of supporting a junction adapter.
The most commonly used MULTI-CLAMP.RTM. systems are labeled with the HC-10, HC-16 and HC-32 Series designations, which support junction adapters for fluid lines on 1.5 inch, 2.0 inch and 3.0 inch centers, respectively. In addition, there are larger MULTI-CLAMP.RTM. series including the HC-46, HC-72 and HC-96 Series designations, which have progressively greater distances between the centers of the fluid lines.
The junction adapters used in conjunction with the MULTI-CLAMP.RTM. systems have undergone great development and improvement in design and manufacturability over the years. For example, early on junction adapters were designed having a multi-piece construction. The junction adapters were formed having a rectangular central support portion, or body, and a separate cylindrical portion.
These rectangular junction adapters were somewhat difficult to manufacture. Several different methods were employed over the years to make them. In the original process, the first step in the manufacturing process was to machine a rectangular block of steel into the height, width and thickness required for the central support portion so that it would be received within the channels of a plural line clamping system. The next step was to drill a hole through the rectangular portion to accommodate the cylindrical portion. Cylindrical bar stock was then machined to form the cylindrical portion. Finally, the cylindrical portion was placed or pressed in the hole in the rectangular portion and brazed to hold it in place.
A second process employed to manufacture the rectangular junction adapter involved using a powdered metal casting for the rectangular portion. Such a casting was formed to the appropriate dimensions with the center hole being pre-formed as part of the casting process. This technique eliminated the need for machining the rectangular portion. However, because the powdered metal did not braze well, a conventional epoxy capable of withstanding temperatures in excess of 200.degree. F. was applied to the joint to secure the machined cylindrical portion to the rectangular portion.
A third process for making the rectangular junction adapters involved using a roll pin, in place of the brazing operation or the epoxy glue operation, to lock the cylindrical portion in place with respect to the rectangular portion. The roll pin was yet another technique for positively securing the cylindrical portion in place with respect to the rectangular portion. However, the production costs associated with the use of a roll pin were quite high due to the extra machining and assembly steps required.
A fourth process for making the rectangular junction adapters utilized a one-piece construction technique which eliminated the effort of assembling the rectangular portion and the cylindrical portion from separate pieces. In this fourth process, a cold forged blank was made in the general configuration of, but which had overall dimensions slightly larger than, the desired finished adapter. The rectangular portion of the blank was then machined to size, and thereafter the cylindrical portion was machined. But, they could not be readily machined on the most economical type of machinery, namely, automatic screw machines. Also, it was considerably more difficult and expensive to machine a forged part than to machine a non-forged part made of mild steel or powdered metal, which increased manufacturing costs.
The next generation junction adapter evolved into a one-piece unit having a hexagonal central support portion that eliminated many of the manufacturing problems and expense associated with the earlier rectangular junction adapters. In this newer configuration, the junction adapter was formed from a single piece of hexagonal bar stock. A significant advantage of this hexagonal junction adapter was that standard sizes of hexagonal bar stock of mild 1008 or 1010 steel already met the necessary dimensions for the central support portion of a junction adapter to fit into a MULTI-CLAMP.RTM. system, thus much of the machining required with the rectangular design was eliminated. Also, the hexagonal bar stock could be easily machined to final configuration by automatic screw machines. Further, because the hexagonal junction adapter was designed to be one-piece, all of the problems of the rectangular junction adapters related to the complex manufacture and assembly of two pieces to form a junction adapter were eliminated.
In recent years, the design of the junction adapter has evolved even further. In particular, the use of junction adapters having face seal fluid connectors, in lieu of the common flare fluid connectors, have become increasingly popular. The face seal fluid connector has become desirable because it exhibits several advantages over the flared fluid connector. For example, face seal fluid connectors can connect to fluid lines operating under as much as 6,000 psi without leaking. Also, these connectors can be repeatedly connected and disconnected to the fluid line without causing any significant detriment to the connector's seal. Further, face seal fluid connectors, unlike some flared fluid connectors, have standard internal diameters that match the fluid lines to which they connect, thereby eliminating any adverse effects on the fluid flow through the junction adapter.
However, junction adapters with face seal fluid connectors used in the MULTI-CLAMP.RTM. systems have presented a new problem. When the junction adapters are located in adjacent positions of the clamping system, the clearance between the adjacent locking nuts that secure the fluid lines to the junction adapters does not permit a wrench or other tool to easily access the flats of the locking nut. This condition is illustrated in FIGS. 1 and 3 of the drawings. As shown in positions A and B of FIGS. 1 and 3, the locking nuts 36 of conventional face seal junction adapters 30 cannot be accessed by a wrench 55 or other tool when they are positioned in adjacent locations A, B in the plural line clamping system 40. As illustrated, clearance X between each junction adapter 30 is extremely small such that wrench 55 is unable to access and torque the locking nut 36. It is important to remember that the face seal fluid connectors on the junction adapters 30 are compression-type connectors that require a substantial amount of torque to be adequately secured. Therefore, anything that inhibits the ability to torque the locking nut 36 and secure the fluid line is extremely undesirable.
The problem as just described has been already experienced with face seal junction adapters in a few of the Series of MULTI-CLAMP.RTM. systems described above, even when the adjacent junction adapters connect different sized fluid lines. For example, in the HC-10 series MULTI-CLAMP.RTM. system where junction adapters connect fluid fittings ranging from 3/8" to 5/8", inadequate clearance conditions can exist between the adjacent junction adapters of 1/2" and 5/8" fluid lines. Similar conditions are also found with certain sizes of junction adapters in the HC-16 and HC-32 series MULTI-CLAMP.RTM. systems.
An important and necessary feature for any new plural line clamping system junction adapter is that it must be capable of being retrofit into the existing plural line clamping systems. As mentioned above, there are currently several tens of thousands of MULTI-CLAMP.RTM. systems in service in the United States and other countries, and each includes several junction adapters. Also, the manufacturer of MULTI-CLAMP.RTM. systems, its distributors and a number of their larger customers each maintain a substantial inventory of MULTI-CLAMP.RTM. systems and components. In addition, conventional plural line clamping assemblies come in several different standard sizes of channels, with each different size channel requiring a different size central support portion. To change the dimensions of the conventional plural line clamping systems would require tooling changes for each such size channel amounting to several millions of dollars for each different size. Thus, any new junction adapter must fit into the existing plural line clamping assemblies or it will not be successful in the marketplace, because it is not realistic to expect the industry to replace completed design or existing plural line clamping systems merely to accommodate a new and superior junction adapter.
In light of the foregoing discussion, it is a principal object of the present invention to provide a high quality junction adapter for use within a conventional plural line clamping system of the type including face seal fluid connectors that will provide adequate clearance for a wrench or other tool to easily access the locking nuts of the fluid fittings of junction adapters positioned in adjacent locations in the plural line clamping system.